Pump for supplying fuel to internal-combustion engines



v a. v. NORDBERG. PUMP FOR SUPFLYING FUEL T0 INTERNAL COMBUSTION ENGINES.

APPLICATION FILED .IULJYI II, I915- RENEWED MAY 8, I9I-9.

Patented Mar. 9,1920.

2 SHEETS-SHEET I- B; v. NORDBERG.

PUMP FOR SUPPLYINGFUEL 'TO INTERNAL COMBUSTION ENGINES. APPLICATION FILED JULY 1. I9l 5- RENEWED MAY 8. l9 l9. 1,333,566, Patented Mar. '9, 1920.

2 SHEETS-SHEET 2- alike nchvN for Supplying Fuel from the T0 all whom it ritay 00mm 1' UNITED. STATES BRUNO V. .NORDBERG, OF MILWAUKEE, WISCONSIN.

PUMP FOIt SUPPLYING'FU EL TO INTERNAL-COMBUSTION ENGINES. I

Application filed July 1, 1915, Serial No; 37,568. Renewed May- Be it known that I, BRUNo ldonnenne, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented certain new and useful Improvements in Pumps to Internal-Combustion Engines, of which the following is a speci- My .present invention pertains to an improved pump for supplying fuel to internal combustion engines and to means for regulating the capacity of said pump.

Two embodiments of the invention are illustrated, more or less diagrammatically in the annexed drawings, wherein:

Figure 1 is a longitudinal-section of one form ofpump embodying my invention;

Fig. 2 a detail plan view of certain por tions thereof; and

Fig. 3 a sectional view embodying a modifiedfprm of the invention.

In internal-combustion engines of the high-compression type, the fuel has to. be forced into the cylinder by means of a pump, and such pump must be so .constructed that it will automatically deliver to the cylinder the exact amount of fuel that is necessary for the load that. the engine carries, and such pump must beprovided with a device. whereby this amount .of fuel may be varied tosuit the variation of the load, giving the motor more fuel when the load increases and less fuel when the load decreases.

It is also desirable and necessary that this regulating device should be under the con trol of an automatic governor,s0 as to render the engine self-regulating. i

The most popular device used for regulating the capacity of thepump in accord-- ance with the demand for fuel is abypass valve,.-whereby part of the fuel is ejected pump and turned'back into the supply, and another art of the fuel forced into the motor cylin er.

Fuel pumps embodying such construction have certain defects, which are eliminated by the present invention. Most pumps heretofore designed for forcing the charge into the engine are so arranged that the excess liquid fuel which the pump takes in during the-suction stroke is discharged through a by-pass valve back into the g ing the first part of the discharge stroke and the remainder of the liquid fuel is then Specification of Letters Patent.

tion valve. which I am aware the suctlon valve can rine engines.

. 2 and fly-Wheel 3. the latter shown in supply ,dur-

8, 1919. Serial No. 295,707.

forced into the motor-cylinder when the bypass valve is closed. In all such devices where the by-pass valve is held open dur-- ing. the early part of it is necessary that ing the latter part that the by-pass part of the suction the discharge stroke such valve be-open durof the suction stroke so valve during the latter In fact, in all such devices of act as a by-pass valve when no separate bypass valve is needed. See patent to Diesel No. 654,140, wherein the by-pas's valve is opened" during the latter endof the suction stroke also acts as a si1c- Patented Mai-.9, 1920.

stroke, and remains open during an equal part of the-discharge stroke.

The liquid fuel is in most cases mineral oil, having considerable viscosity. If such.

fluid the pump, the pump will ceaseapto Work, unless the air can be readily discharged from the space confined by the valves and the plunger. I

I A'fluid of high viscosity will not readily separatei-tself from air mixed therewith, and if the pump is provided with a by-pas's valve as just described," that is, one that is kept open during the latter part of the suction stroke and the early part of the discontains air or develops gases, and if mixture of oil and air is drawn into the charge stroke, the air maybe expelled from I the pump through the bypass valve during the discharge stroke, but during the early part of the following suction stroke it will be sucked back into the pump, and p-articularly Where the fluid in which case, the air does not, readily separate from the oil. This is a very disagreeable feature in pumps of this kind, paris of high viscosity,

ticularly when such pumps are used on ma- 7 In. such. engine installatiofis the 011 may be at times violentlyagitated by the motion of the, sh1p, and if the air enters the fuel ,pumps with the oil and does not. rea-dlly separate, the engines Will stop.

main object of this invention is to -Tht completely overcome such difiiculty, and this may be accomplished by various arrangements,-tWo of which are illustrated, some.

whatdiagrammatically, in the drawings.

, Referring first to Figs. 1 and 2, 1 denotes the driving shaft, provided with a crank part only in ig. 2. The crank has secured to it a connecting-rod 4, which at its inner end is attached to a cross-head.6, fitting and work ing in the outer end of a hollow head or extension 7 of the pump body 8. The plii nger or piston-rod of-the pump is denoted by 9, and is provided at its'inner end witlra piston or head 10 fittingwithin the bore of the suction chamber or cylinder 1]. of the pump, the head being somewhat larger than the rod 9, and normally held in its outermost position, as shown in the drawings, by a heavy spring 12, mounted within the hollow head 7, and bearing at its outer end against the inner face of a washer or disklike member 13, secured to the outer end of the piston-rod. The fuelsupply chamber is.

seat immediately the pressure exerted by the pump falls to that point where it will be overcome by the spring, and oil-pressure in port 19. l

The by-pass port or channel is controlled by two valves, a check-valve 20 and abypass valve 21, the latter moving inwardly to open, while the former moves outwardly to open. A pipe 22 leads from the b-y-pass channel back to the supply chamber 14. Valve 21 is provided with a stem 28, having secured to its upper end a block 24-, slidably mounted in a head 25, the valve being urged to its closed position by a spring 26. Mounted in the head is a rock-shaft 27, having secured to its inner end a tappet 28, the free end of Which overlies block 24 and serves to move the same downwardly to open the valve 21, and to maintain it open for a predetermined interval of time. In operati on, the valvels opened at some point during the. discharge stroke of the pump piston, and

remains open during the early part of the suction stroke.

Suitable means is employed for operating the tappet and to vary the time when it acts upon the block 24 to open the valve. The

throw of the tappet remains practically constant for all variations in load, but the time at which it becomes operative varies with the load, the contact being made earlier for a light load and later for a heavy load, so as to cut out the fuel earlier in the former case and later in the latter case. Any suitable means may be employed to accomplish this result, and in the drawings I have shown the tappetshaft 27 connected by a lever or arm 29 to an eccentric strap 30, through a connecting rod 31. The position of the eccentric upon which the strap is mounted is controlled by a pendulum governor, indicatedas a whole by 32,- and operatively conrected up With the fly-wheel 3 in the usual manner, so. that. the eccentric is advanced when the load is decreased. In other words, the position of the eccentric will be advanced 1111'618131011 to the position of the crank 2', and the cutting out of the; fuel delivery by the earlier opening of-theby-pass valve 21 will theleby take place earlier in the forcing stroke of the pump.

The operation of this form of pump is as follows: WVith the crank 2 in the position shown, all. the valves are closed, and the cylinder ll is filled with liquid fuel, the piston,

in its outward movement under the action of the spring 12, havmg drawn 111 a charge through the inwardly-moving suction valve ,tached piston which, of course, forces the fuel from the pump past the eductio-n valve 18. The discharge of the fuel is quick, or practically instantaneous, which is highly beneficial when an atomizing device is employed to inject the fuel into the motor cylinder.

The eccentric is so set that the tappet 28 acts upon the by-pass valve at some point during the discharge stroke of the piston and by adjustment of the eccentric the point of opening can be regulated as may be necessary, opening early when a small quantity of oil is required, so that during the first part of the discharge stroke the oil is. forced to.

- the motor and during the latter part of the discharge stroke it is returned past the check-valve 20 and by-pass valve 21, through pipe 22 to the supply tank 14.

It is plain that in this device the by-pass valve 21 will also be open during the early part of the suction stroke of the pump and that, in fact, the earlier it opens during the discharge stroke, the later it will close during the following suction stroke. The check valve 20 will, however, prevent the oil from flowing back through the bypass valve into the pump as it seats'toward the pump cylinder and, therefore, under no condition can the by-pass valve become in effect a suction valve. Consequently, if a quantity of oil charged with air is sucked into the pump, part of this mixture will be driven out through the discharge valve 18 and pipe 19 into the motor cylinder and whatever remains will be later discharged through the by-pass valve and pipe 22 to the supply, but during the suction stroke nothing that has passed the check valve 20 can return and, therefore, air can not accumulate -in the P mp- It has been shownin practice that when iso an excess of fuel drawn into the pump has pressure of the engine) such condition.

greatly assists in clearing the pump of air. Experience shows that when oil, highly charged with air, is drawn into the pump, and this oil, during the following discharge stroke is subjected to the pressure within the engine, the air-bubbles are compressed, which, of course, reduces for the moment the quantity that passes through valve 18 and pipe 19. As soon, however, asathe' by-pass valve is opened, the expansive force of the air acts in a manner which quickly clears the pum of air and prevents it from becom.. ing airund. Thus, with a pumpconstructed in accordance with the present in vention, the supply tank can be pumped dry so that the motor actually slows down, but as soon as the supply tank is replenished the pump and motor resume their normal action.

If the same thing should happen in devices of the older type, the pump would become hopelessly air-bound, and would have to be primed before it would again be in condi tion to deliver oil to the motor. In Fig. 3 a different embodiment of the invention is-illustrated.

Similar members are similarly numbered as in Fig. 1, 14 being the tank, 15 the supply pipe, 16 the induction valve, 18 the eduction valve, and 19 the discharge port leading therefrom to the engine cylinder. check-valve 20 and by-pass valve 21 are also present, but are slightly modified in ar-' rangement from those above set forth. The pump body or casing 8 is provided with .an opening in which is mounted a piston or plunger 33 operated from a crank 2 by a connecting rod or pitman 4.

I ing at its lower end upon the upper side of 34 denotes a rod slidably mounted in an opening in the pump casing 8, said rod beara block 35, to which there is secured a stem '36. carrying at its lowerend the by-pass' valve 21. The stem passes through a partition 37, and a spring 38, interposed between the partition and the lower face of the block 35, tends to draw the by-pass valve to its seat. The check-valve 20 in this instance is located'above the by-pass-valve. and a spring '39 urges the check-valve to its seat. The.

upper end of rod 34 is pivotally connected at v40 to a floating'lever 41," one end of said lever being connected to the pump plunger 3-3 at the point 42. The opposite end of the lever is pivotally.connected,'as at 43, .to one end of a link 44, the lower end of the link being, likewise connected to a lever 45 ful crumed at 46 and controlled in its position by a ball; governor 47.

Under this construction the movement of the rod 34 is approximately constant, but themovement of the block 35 varies with The the position of the governor, for the reason that the amount 0 play between the rod and the block varies with the position of the governor. With the parts in the positions shown in full lines, the governor is at its highest point, and as a consequencethe amount of play between said rod and the block isat its minimum, whereby the by- I pass valve 2.1 will be opened early in 1 the ejecting" stroke of the piston33, and as a consequence but a relatively small amount play between the rod or stem 34 and the block 35, and this results in a later opening of the by-pass valve relatively to the stroke of the pump piston, thereby insuring the forcing of the proper quantity of oil to the engine.

The construction just described can be used to advantage where means, other-than the pressure exerted upon the fuelby the pump, as under the construction first set forth, is employed, to atomize the fuel as, y for instance, compressed air at a p'ressureconsiderably higher than that of the oil. In such case the ofiice of the pump is simply to'in ect into the atomizer a certain quantity of oil veryearly in the stroke. Under botli' constructions the by-pass valve is prevented by the check-valvefrom acting as a suction or induction valve and in each case the.

pump clears itself of air.

In the use of the term piston in referring to the members 10 and 33 it is to be understood as denoting any element,

whetherit be a true piston or not, which acts to draw in and force the fuel from the pump chamber. v

, Having thus described my invention, what I claim is:

1. A pump for forcingfuel into an internal-combustion engine, comprising in combination a'piston; an eduction valve; an intake or suction valve; a bypass valve opening from the pumpchamber and controlling a passage leading therefrom to the, source of supply, and a check-valve acting to close such passage upon the completion of the ejecting stroke of the piston.

2.: A- pump for forcing fuel into an internal-combustion engine, comprising in combination a piston; an eduction valve; an

intake or suction valve; a by-pass valve opening from the pump chamber and con trolling a passage leading therefrom to the source of supply; means, respons1ve to the requirements of the engine, for controlling combination a piston; an eduction valve;-

an intake or suction valve; a check-valve controlling the reverse flow of fuel through a-channel leading from the pump chamber and normally seating during the suction of the piston; and a governor-controlled bypass valve, regulating the discharge of fuel through said channel.

4. A pump for forcing oil into an internal combustion engine, comprising in combination, a piston; an intake valve; an eduction; valve; and means for controlling the amount of fuel forced by the piston through the eduction valve, said means being under tne control of and actuated by the engine and serving to eject the remaining portion of the fuel and the entrained or contained air from the pump thereby preventing accumulation of air in the air binding thereof. 5. In an-apparatus for supplying a varipump and consequent able quantity of fuel to an internal-combustion engine, the combination with the fuel supply; of fuel-forcing means communicating therewith and supplying at the beginning of each working stroke of the engine ah excess of fuel under pressure greater than the back pressure of the engine; and means under the control of the engine for allowing the excess fuel, still under pressure, to return to the fuel supply during the latter portion of the feeding or supplying stroke of the fuel-forcing means. 6. In an apparatus for supplying a variable quantity of fuel to an internal-combustion engine, the combination with the fuel supply; of a pump operated bythe engine, the pump-chamber being provided with a suction valve, a fuel feed valve, and

a bypass valve, the by-pass' valve normally opening at a pressure equal to or greater than that existing in the engine cylinder; and means for preventing a return flow of fuel into the pump past the by-pass valve during the suction stroke of the pump.

7. In an apparatus for forcing fuel into an internal combustion engine, the combination of a pump piston; means for impart ing a suction stroke thereto and opposing the inward movement thereof; a reciprocating member normally spaced away from thepiston; means for actuating said member and brmglng 1t into contact wlth the piston under high initial speed and to iman internalcombustion engine, the combina-' tion of a pump piston; means for imparting asuction stroke thereto and opposing the inward movement thereof; a reciprocating member normally spaced away from the piston; means for actuatlng said member and bringing it into contact with the piston under high initial speed and to impart a fuel-ejecting stroke thereto; a bypass valve opening during the ejecting stroke ofthe piston and closing during the suction stroke thereof; and a check-valve preventin influx of fuel'past the by-pass valve during the suction stroke of the piston.

9. In an apparatus for forcing fuel into an internal-combustion engine, the combination of a pump piston; means for impart ing a suction stroke thereto and opposing the inward movement thereof; a reciprocating member normally spaced away from the piston; means for actuating said member and bringing it into contact with the piston under high initial speed and to impart a fuel-ejecting stroke thereto; a by-pass valve opening only during the latter part of the ejecting stroke of the piston and closing during the suction .stroke thereof; and means under the control of the engine for timin the opening and closing of the bypass valve.

10-. In an apparatus for forcing fuel into an internal-combustion engine, the combination of a pump piston; means for imparting a suction stroke thereto and opposing the inward movement thereof; a reciprocating member normally spaced away from the piston; means for actuating said mem ber and "bringing it into contact with the piston under high initial speed and to im-.

part a fuel-ejecting stroke thereto; a bypass valve opening during the ejecting stroke of the piston and closing during the suction stroket thereof; a-check-valve preventing influx of fuel past the by-pass valve during the suction stroke of the piston; and

12. In an apparatus for forcing fuel into an internal-combustion engine, the combination of a pump; a moving actuating element for said pump operated-from the engine, said element and pump having a lost-motion connection whereby the actuating element may obtain a high initial speed prior to actuating the pump; a by-pass valve for the pump, opening only during the latter portion of the discharge stroke of the piston; and means controlled by the operation of the engine for timing the opening and 0105- 10 ing of the by-pass valve.

In testimony whereof I have signed my name to this specification.

BRUNO V. NORDBERG. 

